The specific problem proposed is the study of the utilization and coordination of the cat's hindlimb muscles during a maximal vertical jump. This problem was chosen because it is an especially good vehicle for using a combination of optimal control techniques and experimental measurements in the intact animal for the study of complex movements. An optimal control model of the jumping cat will be developed and solved computationally. The computed solution will be compared with the experimental data. These comparisons can then be used to modify if necessary the mathematical model and to suggest additional experimental investigations. These results will facilitate our understanding of the coordination of hindlimbs during intact animal movement and further study of normal movement in other mammals including man.